High capacity liquid contact electrical switch



3,155,794 HIGH CAPACITY LIQUID CONTACT ELECTRICAL SWITCH Filed Aug. 2, 1962 D. T. EU DALY 2 Sheets-Sheet 1 Nov. 3, 1964 l N VEN TOR. BYo/r/ Z-aw/ fig/ a w fw. i i 47% y f fn/ v in t a. .W4 E m :1, l; ..nh 2 l l i.- m /,v,. vv,ww m IWIAVAZA 2 M j 2 y @/K m ,W ,M// ,.X/ l 2 i 21W/ 7 .IIL f a g d, f n f ,l @//Q i w M n W. M/ uw V'l y d. f l w @m 7 Nov. 3, 1964 D. T. EU DALY 3,155,794

HIGH CAPACITY LIQUID CONTACT ELECTRICAL SWITCH Filed Aug. 2, 1962 2 Sheets-Sheet 2 United States Patent O 3,155,794 HIGH CAPACITY LIQUID EUNTACI ELECTRICAL SWIICII Don T. En Daly, Harlingen, Tex. Filed Aug. 2, 1962, Ser. No. 214,295 Claims. (-Cl. 2ML-M2) The present invention relates to a switch for 1a high voltage and high amperage current.

An object of the present invention is to provide a switch of high capacity which has no moving parts which carry current, one which is sealed against dirt and fumes, one which requires little or no maintenance, and one which is economically feasible.

Another object of the present invention is to provide a high capacity electrical switch which may be shipped dry or shipped filled with the operating liquid, mercury, and one which may be handled and placed in position so as to activate it fand to remain activated as long as it in the upright position.

A further object of the present invention is to provide a high capacity electrical switch which may be used as a current limiting switch, one which may be used as a current limiting switch with either A.C. current or DC. current, and one which has indicating means for showing when the switch has been overloaded and thrown to the out position.

These and other objects and advantages of the present invention will be apparent to a person skilled in the art from the following description when taken in connection 1 with the annexed drawings, in which:

FIGURE l is an elevational view partially in section showing the switch of the present invention in operating condition,

FIGURE 2 is a view similar to FIGURE 1 showing the switch in open or inoperative position,

FIGURE 3 is a View taken on the line 3 3 of FIG- URE l,

FIGURE 4 is a view taken on the line 4 4 of FIG- URE 3,

FIGURE 5 is a View taken on the line 5 5 of FIG- URE 3,

FIGURE 6 is =a fragmentary elevational view partially in section showing how the switch is reset for operation,

FIGURE 7 is a fragmentary View similar to FIG- URE 3 showing another embodiment of the present invention, and

FIGURE 8 is a view on an enlarged scale, taken on line 8 8 of FIGURE 7.

Referring in detail to the drawings in which like numerals indicate like parts throughout the several views, the present invention consists in an upright casing 10 having side walls I2 and I4, end walls I6 and I8, and a bottom 2li.

Adjacent the end wall I8 within the casing Iii is a well 22 having its upper open end spaced from the upper ends of the side walls and end walls of the casing lil. Projecting upwardly through the bottom 24 of the well 22 is a post 26 through which extends a contact element 28 having the upper end portion free of the post 26.

A charge of mercury, as at 3u, is contained within the well 22.

An inverted cup 32, fabricated of a non-conductive material, is normally positioned so that the rim 34 thereoi` is spaced above the contact portion 28. The cup 32 is connected to the casing lil for movement from the normal position, shown in FIGURE 1, to a position shown in FIGURE 2 in which the rim 34 is below and spaced from the contact element portion 23.

Inwardly of and spaced from the other end wall I6 and adjacent the upper end of the side walls I2 and 14 is an actuating rod 3o having end portions exteriorly or" the side walls 12 and I4, as at 38 and 40, respectively. The rod end portion 40 has an actuating handle 42 connected thereto.

A pair of arms 44 and 45 project outwardly from the rod 35 and are formed integrally with sleeves 45 and 47, respectively, which are circumposed about the rod 36 within the casing lil. Pins 43 carried by the free ends of the arms 44 and 46 support the cup 32 for its upward and downward movement responsive to swinging movement upwardly and downwardly of the arms 44 and 4d.

A pin Sti extends between the arms 46 and 44 and is supported thereby and between the arms 44 and 46 is a roller 52 mounted on the pin 50.

Circumposed about the portion of the rod 35 between the arms 44 and 46 is a sleeve 53 formed integrally with an arm 54 of L-shaped configuration. rIhe short leg 56 of the arm S4 forms a stop for one leg of an L-shaped lever 58 pivotally connected to the long leg o0 of the arm 54 by means of a pivot pin 52, as shown most clearly in FIGURES 1 and 2.

The other leg of the lever 5S is pivotally connected by a link 64 to the upper end of a vertically disposed solenoid core 65, the solenoid 68 being mounted within the casing Ill on the bottom Ztl thereof.

A spring 7d within the solenoid 68 biases the core 6d to the up position shown in FIGURE 1.

An electrical connector 72 having a portion 74 exteriorly of the wall I6 is embedded in the bottom 2@ of the casing l0 and is formed into a helix, at 76, within the solenoid 68. The connector 72 extends from the helix 76 to the contact element portion 28. A ring 78 surrounds the lower end of the post 26 and rests upon the bottom of the well 22. The ring 78 is a connector having a portion 8) exteriorly of the casing l'itl adapted for connection to an electrical conduit, as at 32 in FIGURE 2.

A cover 34 extends over the upper ends of the side walls I2 and I4 and the end walls 16 and I8 and is secured thereto by machine screws 86. Projecting upwardly from the cover is a sleeve 88 forming a support for an indicator rod @il having an indicator or iiag 92 on the upper end thereof and having the lower end extending into the casing I@ and threadedly engaged in the bottom of the inverted cup 32. A spring 94 within the sleeve 88 biases the rod 9i) downwardly, there being provided a collar 96 on the rod 99 against which one end of the spring 96 bears, the other' end of the spring bearing against a screw cap 9S which closes the upper end of the cylinder or sleeve S8.

In addition to the charge of mercury 3d contained within the casing lil, there is a charge of a lighter liquid having spark quenching characteristics, as at lili) in FIG- URES l and 2 and 4 to 6. The liquid of the charge 100 may be transformer oil, sulphur hexailuoride, or the like. A conductive ring 102 surrounds the contact element portion 28 and is secured to the upper end of the post 26.

In operation when the casing lil is to be installed it is tilted so that all the mercury flows down to the end of the casing having the well 22 and then it is tilted back so that the mercury stays within the well 22 while the other liquid lls the rest of the casing I@ and the space above the cup 32. The cup 32 will also have some of the liquid therein. Upon the forward access current through the solenoid 68 as received from the conductor or connector 72 and traveling through the helix 76, the solenoid core 66 will be drawn downwardly so as to rotate the lever 53 in the counter-clockwise direction from the position shown in FIGURE 1 to the position shown in FIGURE 2. This results in release of the roller S2 fromits support on the short leg of the lever 5S and subsequent dropping vof the arms 44 and 46 under the action of the spring 94.

This results in forcing of the cup 32 downwardly over the exposed contact portion 28 so as to drive the mercury out of the cup .'52 and upwardly along the sides of the cup 32 in the well 22. As the mercury leaves the contact of the ring lltlZ any spark between the mercury and the ring 102 will be quenched by the transformer oil of the charge it?.

The switch of the present invention will be then in an out condition and the indicator iag 92 will be the lower position so that an operative after correcting the condition which led to the overcharge of the switch may by rotating the handle 42 downwardly so as to rotate the arm ft in a clockwise direction from the position shown in FGURES 1 and 2 to the position shown in FIGURE 6. This results in re-cocking of the lever 5S so that when the handle ft2 is returned to the up position the short leg of the lever 58 will again engage the roller 52 and lift the arms 44 and 46 to the up position drawing the cup 312 upwardly and again letting the mercury charge Sil reestablish electrical contact between the contact portion 2S and the ring 78.

In FIGURES 7 and 8, the solenoid is not employed and the arms 44' and 4o are connected directly through the rod 3d to the handle all. A detent assembly lil@ serves to retain the switch in either the operative condition or the inoperative condition, there being provided two indent recesses in the casing wall, as at tile and 1% in FiG- URE 8.

The use of the second form of the invention is obvious to a person skilled in the art, as being possible to stop the flow of current through the switch by manipulating the handle 42 downwardly and to re-establish current iiowing through the switch by lifting the handle 42.

While only preferred embodiments of the present invention are shown and described other embodiments are contemplated and numerous changes and modifications may be made therein without departing from the spirit of the invention as set forth and established by the appended claims.

What is claimed is:

1. An electrical switch comprising an upright casing including a bottom, opposed side walls rising from said bottom, an end wall connecting each of the adjacent ends of said side walls together and a top extending over the upper ends of said side walls and end walls, a well in said casing, said well having the open upper end thereof spaced below said casing top, a contact element in said well and having a portion spaced above the bottom of said well, an inverted cup mounted within said casing for upward and downward movement between 1a position in which the rirn thereof is above and spaced from said contact element portion and a position in which said cup encompasses said element with the rim below and spaced from said element portion, a charge of electrically conductive liquid in said well and contacting said element when said cup is in the above position, said cup when in the down position being operable to force said liquid out of contact with said element, electrical connection means extending through said casing into Contact with said liquid and into connection with said element, and releasable latch means operatively connected to said cup for holding said cup in the above position.

2. An electrical switch comprising an upright casing including la bottom, opposed side walls rising from said bottorn, an end wall connecting each of the adjacent ends of said side walls together and a top extending over the upper ends of said side walls and end walls, a well in said casing, said well having the open upper end thereof spaced below said casing top, a contact element in said well and having a portion spaced above the bottom of said well, an inverted cup mounted within said casing for upward and downward movement between a position in which the rim thereof is above and spaced from said contact element portion and a position in which said cup encompasses said element with the rim below and spaced from said element portion, a charge of electrically conductive liquid in said well and contacting said element when said cup is in the above position, said cup when in the down position being operable to force said liquid out of contact with said element, electrical connection means extending through said casing into contact with said liquid and into connection with said element, spring means operatively connected to said cup urging said cup to the down position, and releaseable latch means operable to released position upon a iiow of current above a predetermined value through the connection means connected to said element operatively connected to said cup for holding said cup in the above position.

3. An electrical switch comprising =an upright casing including a bottom, opposed side walls rising from said bottom, an end wall connecting each oi' the adjacent ends oi said side walls together and a top extending over the upper ends of said side walls and end walls, 1a well in said casing, said well having the open upper end thereof spaced below said casing top, a contact element in said well and having a portion spaced above the bottom of said well, an inverted cup mounted within said casing for upward and downward movement between a position in which the rim thereof is above and spaced from said contact element portion and a position in which said cup encompasses said element with the rim below and spaced from said element portion, a charge of electrically conductive liquid in said well and contacting said element when said cup is in the above position, said cup when in the down position being operable to force said liquid out of contact with said element, electrical connection means extending through said casing into contact with said liquid and into connection with said element, spring means operatively connected to said cup urging said cup to the down position, and releasable' latch means including a solenoid operable to released position upon a flow of current above a predetermined value through the connection means connected to said element operatively connected to said cup for holding said cup in the above position.

4. The apparatus according to claim l in which said liquid charge is mercury.

5. The apparatus according to claim 4 together with a charge of other liquid floating on said mercury, said other liquid having a spark-quenching characteristic.

No references cited. 

1. AN ELECTRICAL SWITCH COMPRISING AN UPRIGHT CASING INCLUDING A BOTTOM, OPPOSED SIDE WALLS RISING FROM SAID BOTTOM, AN END WALL CONNECTING EACH OF THE ADJACENT ENDS OF SAID SIDE WALLS TOGETHER AND A TOP EXTENDING OVER THE UPPER ENDS OF SAID SIDE WALLS AND END WALLS, A WELL IN SAID CASING, SAID WELL HAVING THE OPEN UPPER END THEREOF SPACED BELOW SAID CASING TOP, A CONTACT ELEMENT IN SAID WELL, AND HAVING A PORTION SPACED ABOVE THE BOTTOM OF SAID WELL, AN INVERTED CUP MOUNTED WITHIN SAID CASING FOR UPWARD AND DOWNWARD MOVEMENT BETWEEN A POSITION IN WHICH THE RIM THEREOF IS ABOVE AND SPACED FROM SAID CONTACT ELEMENT PORTION AND A POSITION IN WHICH SAID CUP ENCOMPASSES SAID ELEMENT WITH THE RIM BELOW AND SPACED FROM SAID ELEMENT PORTION, A CHARGE OF ELECTRICALLY CONDUCTIVE LIQUID IN SAID WELL AND CONTACTING SAID ELEMENT WHEN SAID CUP IS IN THE ABOVE POSITION, SAID CUP WHEN IN THE DOWN POSITION BEING OPERABLE TO FORCE SAID LIQUID OUT OF CONTACT WITH SAID ELEMENT, ELECTRICAL CONNECTION MEANS EXTENDING THROUGH SAID CASING INTO CONTACT WITH SAID LIQUID AND INTO CONNECTION WITH SAID ELEMENT, AND RELEASABLE LATCH MEANS OPERATIVELY CONNECTED TO SAID CUP FOR HOLDING SAID CUP IN THE ABOVE POSITION. 